This invention relates generally to control cables and more particularly has reference to a universal control cable having variable travel length and variable types of end fittings.
Conventional control cables have a flexible core slidably supported within a flexible conduit. A rigid actuator rod extends from the end of the core through a rigid hub on the end of the conduit and is connected to a source of power which imparts axial movement to the actuator and core.
The actuator and hub are commonly referred to as end fittings. Various sizes and types of end fittings are known. Examples include clamp ends, bulkhead ends, remote valve control input and output ends, modulator cable ends, vernier ends and positive lock ends. The configuration and size of the end fitting determines the suitability of the cable assembly for a given application. The end fitting also determines the travel length of the cable assembly.
It is current practice to permanently fix the end fittings to the core and conduit during manufacture. As a result, existing cables are of a fixed type and have a fixed travel length. Distributors who supply control cables to users having differing needs are thus forced to stock large inventories of complete cable assemblies for each different type and travel length of control cable. This can cause serious problems.
Similar problems are experienced by a user who has a need for several different types of control cables. He must stock a separate inventory of complete cable assemblies for each of his needs. In addition, he will be forced to replace entire cable assemblies if he has an application which requires different types of control cables at different times.
A need exists for a universal cable which can be readily adapted to different uses in the field.
Pertinent U.S. and foreign patents are found in Class 74, subclasses 486, 487 and 501-503; Class 138, subclasses 118, 137 and 140; and Class 403, subclass 49 of the official classifications of patents in the U.S. Patent and Trademark Office.
Examples of pertinent patents are U.S. Pat. Nos.
3,287,990 PA1 3,945,268 PA1 3,960,032 PA1 3,393,587 PA1 4,161,993 PA1 4,238,975 PA1 4,177,691 PA1 3,955,441 PA1 3,985,041 PA1 3,289,491 PA1 3,411,373 PA1 4,175,450 PA1 4,173,157 PA1 3,855,817 PA1 4,304,148 PA1 3,320,665 PA1 3,516,299 PA1 3,587,341 PA1 4,203,430 PA1 3,988,943 PA1 3,662,617 PA1 4,304,149
U.S. Pat. No. 3,287,990 shows threads at distal ends of hub assemblies and at distal ends of rods. In the hub assembly, a cylindrical member is threaded onto a tubular member and the tubular member is part of the hub assembly which is crimped onto the conduit.
U.S. Pat. No. 3,985,041 has threaded connectors crimped on ends of conduits for receiving an adapter. A threaded connector crimped onto the core receives the threaded end of a core from a second push-pull cable.
U.S. Pat. No. 3,320,665 shows a fitting having a plurality of annular grooves which are crimped down onto the outer cover of the conduit to effect a seal between the fitting and the cover.
The remaining patents are less pertinent.
None of the cited patents discloses a control cable assembly having variable end fittings.